A man walks to a view point and returns to the starting point by his car maintaining constant speed and thus takes a total time of 9 hours 15 minutes. He would have gained 2 hours by driving both ways. How long would it have taken for him to walk both ways with same walking speed?

Correct option is B

Given:
Walking one way + Driving one way = 9 hours 15 minutes
Driving both ways = 9 hours 15 minutes - 2 hours = 7 hours 15 minutes
Solution:
Let 'w' be the time taken to walk one way, and 'd' be the time taken to drive one way.
w + d = 9 hours 15 minutes = 9.25 hours.
2d = 7 hours 15 minutes = 7.25 hours.
Therefore, d =$$\frac{ 7.25 }{ 2 }=$$​ 3.625 hours.
Substitute d in the first equation: w + 3.625 = 9.25.
w = 9.25 - 3.625 = 5.625 hours.
Time to walk both ways = 2w = 2 $$\times$$​ 5.625 = 11.25 hours.
11.25 hours is 11 hours and 0.25$$\times$$60 minutes which is 11 hours and 15 minutes.​
Therefore, it would have taken him 11 hours and 15 minutes to walk both ways.